Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur

  title={Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur},
  author={Johan Lindgren and Peter Sj{\"o}vall and Volker Thiel and Wenxia Zheng and Shosuke Ito and Kazumasa Wakamatsu and Rolf Bernhard Hauff and Benjamin P. Kear and Anders Kokkvoll Engdahl and Carl Alwmark and Mats E. Eriksson and Martin Jarenmark and Sven Sachs and Per Erik Ahlberg and Federica Marone and Takeo Kuriyama and Ola Gustafsson and Per Malmberg and Aur{\'e}lien Thomen and Irene Rodr{\'i}guez-Meizoso and Per Uvdal and Makoto Ojika and Mary Higby Schweitzer},
Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales. Here we show that this resemblance is more than skin deep. We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius. Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically… 

Crypsis in the pelagic realm: evidence from exceptionally preserved fossil fish larvae from the Eocene Stolleklint Clay of Denmark

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Two excellently preserved specimens of Mixosaurus cornalianus from the Anisian layers of the Middle Triassic Formazione di Besano, with soft parts associated with well-articulated skeletal elements,

Integumentary structure and composition in an exceptionally well-preserved hadrosaur (Dinosauria: Ornithischia)

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Stenopterygiids from the lower Toarcian of Beaujolais and a chemostratigraphic context for ichthyosaur preservation during the Toarcian Oceanic Anoxic Event

Abstract We report new ichthyosaur material excavated in lower Toarcian levels of the LafargeHolcim Val d'Azergues quarry in Beaujolais, SE France. A partially articulated skull and a smaller,

Re-appearance of hypercarnivore ichthyosaurs in the Cretaceous with differentiated dentition: revision of ‘Platypterygius’ sachicarum (Reptilia: Ichthyosauria, Ophthalmosauridae) from Colombia

A large number of character differences and revised phylogenetic relationships are used to remove the Colombian taxon from Platypterygius and recognize it as a new genus, Kyhytysuka sachicarum comb, which opens new questions regarding the diversity and paleobiogeography of Early Cretaceous ichthyosaurs from northern Gondwana.

Recent advances in amniote palaeocolour reconstruction and a framework for future research

This review focused on fossil amniotes produces an overarching framework that appropriately reconstructs palaeocolour by accounting for the chemical signatures of various pigments, morphology and local arrangement of pigment‐bearing vesicles, pigment concentration, macroscopic colour patterns, and taphonomy.

Taphonomic and Diagenetic Pathways to Protein Preservation, Part II: The Case of Brachylophosaurus canadensis Specimen MOR 2598

Simple Summary Reports of the recovery of proteins and other molecules from fossils have become so common over the last two decades that some paleontologists now focus almost entirely on studying how

Exceptionally preserved ‘skin’ in an Early Cretaceous fish from Colombia

Preservation of ‘skin’ with chemical and molecular characterization from a three-dimensionally preserved caudal portion of an aspidorhynchid Cretaceous fish from the equatorial Barremian of Colombia is reported, increasing the number of localities for which exceptional preservation is known.

A polar dinosaur feather assemblage from Australia




Biochemistry and adaptive colouration of an exceptionally preserved juvenile fossil sea turtle

The holotype (MHM-K2) of the Eocene cheloniine Tasbacka danica is arguably one of the best preserved juvenile fossil sea turtles on record and provides direct chemical evidence that adaptive melanism had evolved 54 million years ago.

Skin pigmentation provides evidence of convergent melanism in extinct marine reptiles

This work presents direct chemical evidence of pigmentation in fossilized skin, from three distantly related marine reptiles: a leatherback turtle, a mosasaur and an ichthyosaur, and provides evidence of convergent melanism in three disparate lineages of secondarily aquatic tetrapods.

Osteohistology of the Early Triassic Ichthyopterygian Reptile Utatsusaurus hataii: Implications for Early Ichthyosaur Biology

The first osteohistological data concerning the most basal ichthyopterygian yet known, Utatsusaurus hataii, from the Lower Triassic of Japan is presented, and the cancellous bone structure suggests adaptation to active swimming in an open marine environment.

On the purported presence of fossilized collagen fibres in an ichthyosaur and a theropod dinosaur

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Structure of the integument of southern right whales, Eubalaena australis

The gross and histological structure of the southern right whale integument is described and compared with terrestrial mammals and previous descriptions of mysticete (baleen whale) and odontocete (toothed whale) species, and surprisingly, the integument of balaenids (right and bowhead mysticetes) in general is more like that of Odontocetes than that of the more closely related balAenopterids (rorqual mysticete).

Microscopic and immunohistochemical analyses of the claw of the nesting dinosaur, Citipati osmolskae

It is shown that fossil tissues respond with the same specificity, though less intensity, as those from living birds, and that calcium chelation greatly increased antibody reactivity, suggesting a role for calcium in the preservation of this fossil material.

Regulation of Body Temperature by Some Mesozoic Marine Reptiles

Data distribution reveals that these large marine reptiles were able to maintain a constant and high body temperature in oceanic environments ranging from tropical to cold temperate, and suggest high metabolic rates required for predation and fast swimming over large distances offshore.

Evolution of Fish-Shaped Reptiles (reptilia: Ichthyopterygia) in Their Physical Environments and Constraints

Ichthyosaurs were a group of Mesozoic marine reptiles that evolved fish-shaped body outlines that allowed estimation of such characteristics as optimal cruising speed, visual sensitivity, and even possible basal metabolic rate ranges.

Preservation of uropygial gland lipids in a 48-million-year-old bird

Analysis of lipid residues from the uropygial gland of an early Eocene bird using pyrolysis gas chromatography mass spectroscopy shows the resilience of lipids over geologic time and their potential role in the exceptional preservation of lipid-rich tissues of macrofossils.

Molecular evidence of keratin and melanosomes in feathers of the Early Cretaceous bird Eoconfuciusornis

This work represents the oldest ultrastructural and immunological recognition of avian beta-keratin from an Early Cretaceous (∼130-Ma) bird and sheds new light on molecular preservation within normally labile tissues preserved in fossils.